It decreases the amount of light and the proportion of blue light on your computer screen as the actual sun goes down.

Thus, a very important part of getting proper sleep is having a nightly ritual that involves relaxation at low light. I would assume that similar to expecting that you will eat, having a ritual before sleep will help your body make the proper internal adjustments towards sleep.

When you sleep, it’s best to sleep in the dark. Moonlight can be helpful for regulation of feminine cycles, otherwise light should be avoided during sleep.

Reciprocally, getting exposure to sunlight or blue light when you wake up, or best case scenario waking up to the actual sun, is a great idea.

Additionally, during the day, exercise and sun exposure can help with the same hormonal/stress mechanisms that effect sleep. Plus, sun exposure is a great way to create vitamin D (a complex of hormone-precursors that aren’t necessarily provided by supplementation nor most diets).

Finally some other tips: avoid sugar/caffeine in the evening, especially if you are sensitive; siesta of about 30 minutes in the afternoon is okay but avoid late naps; eat some minor amount of protein within about an hour of waking (this isn’t so much sleep hygiene as much as a sugar-regulation issue–but sugar regulation itself is important)–similarly you <might> wake up for sugar-disregulation at night, if so, try something like nuts in the evening for the fiber/protein that can help sustain your body through the night.

Most of our self-healing occurs during sleep. Thus, sleep can play an important role in keeping us happy and healthy. Hopefully some of the above can help.